Test bench assembly for the simulation of cardiac surgery and/or interventional cardiology operations and/or procedures

ABSTRACT

A test bench assembly ( 10 ) for the simulation of cardiac surgery and/or interventional cardiology operations and/or procedures, comprising a passive heart ( 12 ), wherein said passive heart ( 12 ) is an explanted or artificial or hybrid heart, said passive heart ( 12 ) having at least one pair of cardiac chambers ( 14, 16; 114, 116 ) comprising an atrial chamber ( 14; 114 ) and a ventricular chamber ( 16; 116 ); a reservoir ( 20 ), adapted to house the working fluid; a pressure generator ( 22 ), adapted to provide said passive heart ( 12 ) pumping said working fluid with the pumping function, said pressure generator ( 22 ) being fluidically connected both to said ventricular chamber ( 16 ) of said passive heart ( 12 ) and to said reservoir ( 20 ) by means of first fluid connection means; a pressure regulation device ( 24 ) which provides the working fluid in input to the atrial chamber ( 14 ) with the preload pressure, and the working fluid in output from the ventricular chamber ( 16 ) with the afterload pressure, said pressure regulation device ( 24 ) being fluidically connected both to said atrial chamber ( 14 ) of said passive heart ( 12 ) and to said ventricular chamber ( 16 ) of said passive heart ( 12 ) by means of second fluid connection means; wherein said pressure regulation device ( 24 ) comprises a single compliant element ( 26 ) for each pair of cardiac chambers ( 14, 16 ) which provides the working fluid with both the preload and the afterload pressures.

FIELD OF THE INVENTION

The present invention relates to a test bench assembly for thesimulation of cardiac surgery and/or interventional cardiologyoperations and/or procedures.

BACKGROUND ART

One of the purposes of training for cardiac surgeons and forinterventional cardiologists is to provide clinical personnel with acertain familiarity and acquaintance with the particular physiologicalconditions they will have to confront in the course of an interventionwhich involves the beating heart of a living patient. The aspects whichcan mainly interfere with the intervention of the clinical operator areof a fluid dynamic nature and due to blood circulation, to the openingand closing of the heart valves and to the deformation of the organduring the cardiac cycles. Hence, there is a need to provide a testbench able to faithfully replicate the physiological conditions of thecardiac cycle.

The four cardiac chambers comprise two atria and two ventricles, inwhich each atrium receives the blood coming from body tissues and flowsin a ventricle which in turn flows in an artery. The left atrium and theleft ventricle, separated by the mitral valve, form the left heart,which receives blood from the lungs and pumps it in the body, whileright atrium and right ventricle form the right heart which receivesblood from the body and transmits it to the lungs.

Generally, known test benches comprise a heart from a human or animaldonor, for example hearts of porcine origin. This heart is generallyexplanted by cutting the blood vessels directly connected to the atriaand to the ventricle but leaving intact a section of the veins and ofthe arteries as well as the native cardiac valves. Such an explantedheart is incapable of contracting spontaneously to pressurize the fluidreceived in the cardiac chambers which determines the opening of thecardiac valves to carry out the pumping action for which it is intendedin vivo. Therefore, said explanted heart is connected to a pumpingsystem provided in the test bench and comprising one or more pulsatilepumps, as well as a system of hydraulic conduits and containers whichsimulate the hydraulic impedances out of the heart and into the heart.

Usually, the pumping system is connected to the explanted heart bymaking a hole in the wall of the heart, usually in the apical portion ofthe heart, and providing a conduit which flows directly into theventricular chamber. Through this piping the pumping system pressurizesfluid within the ventricular chamber to determine the opening of theaortic outflow valve, out of the left ventricle. Downstream of theaortic valve out of the left ventricle, a piping is provided beingconnected to a hydraulic impedance and an afterload container, in orderto simulate the systemic impedance seen by the heart when it ejects theblood.

Known test bench solutions have been designed to model by means of asystem of four impedances and four respective containers both the fluiddynamic impedance which the heart sees during the ejection of blood fromthe ventricle, known as afterload, and the pressure due to the bloodreturning to the atria, known as preload. In these known solutions, ithas been opted to realize as many impedance simulation systems as thereare cardiac chambers, because the preload pressure of the fluid flowinginto the atria is far lower than the afterload pressure which the bloodsees in ejection. For example, solutions of this type are shown in thedocuments US-2011-0217684, US-2013-0288218, US-2014-0370490,US-2014-0099620, US-2015-0024362 and the non-patent disclosure Andrew L.Richards et al.: “ A Dynamic Heart System to Facilitate the Developmentof Mitral Valve Repair Techniques” (ANNALS OF BIOMEDICAL ENGINEERING,KLUWER ACADEMIC PUBLISHERS-PLENUM PUBLISHERS, NE, Vol. 37 No. 4. 18February 2009).

Solutions of this kind impose large dimensions of the test bench andrequire the presence of highly qualified personnel to manage them duringthe installation and utilization of the test bench. These aspects makethe test bench difficult to transport, forcing the heart surgeon to goto the place where the test bench is installed. At the same time, thistype of test benches is substantially impossible to put in operationwithout the intervention of specialized technical personnel, forcing thetechnical personnel to go to the place where the test bench isinstalled.

Thus, there is a strongly felt need to provide a test bench solutionwhich faithfully reproduces the physiological conditions without therebybeing bulky or complicated to operate.

There is a need to provide a test bench solution which allows to reducethe installation and operation costs of the test bench compared to knownsolutions, without thereby resulting in diminished functionality orreliability.

There is a need to provide a test bench with a reduced number ofcomponents and with reduced size compared to known solutions, withoutthereby resulting in diminished functionality or reliability.

There is a strongly felt need to provide a test bench solution whichfaithfully reproduces the physiological conditions while allowing toreduce the costs associated with the procedures for training the heartsurgeon/interventional cardiologist.

SOLUTION

It is one object of the present invention to overcome the drawbacks ofthe prior art mentioned hitherto and to provide a solution to the needsstated with reference to the background art.

This and other objects are achieved by an assembly according to claim 1.

Some advantageous embodiments are set forth in the dependent claims.According to an aspect of the invention, a test bench assembly for thesimulation of cardiac surgery and/or interventional cardiologyoperations comprises: a passive heart, in which said passive heart is anexplanted or artificial or hybrid heart, said passive heart having atleast one pair of cardiac chambers, comprising an atrial chamber and aventricular chamber;

a reservoir, adapted to house the working fluid; a pressure generator,adapted to provide the pumping function to said passive heart by pumpingsaid working fluid, said pressure generator being fluidically connectedboth to at least one ventricular chamber of said passive heart and tosaid reservoir by means of first fluid connection means; a pressureregulation device which provides the working fluid in input to theatrial chamber with the preload pressure, and the working fluid inoutput from the ventricular chamber with the afterload pressure, saidpressure regulation device being fluidically connected both to saidatrial chamber of said passive heart and to said ventricular chamber ofsaid passive heart by means of second fluid connection means.

According to an aspect of the invention, said pressure regulationcomprises a single compliant element for each pair of cardiac chambers,which provides the working fluid with both the preload and the afterloadpressures.

According to an aspect of the invention, said pressure generatorcomprises at least one flow intercepting element, for example a solenoidvalve, which selectively allows direct fluid connection between saidpassive heart and said reservoir.

According to an aspect of the invention, said pressure generatorcomprises a kinetic stationary flow rate pump, for example a centrifugalpump.

According to an aspect of the invention, said first fluid connectionmeans comprise at least one conduit which flows into the interior ofsaid ventricular chamber of the passive heart, and said conduitcomprises an anchoring plug which can be fitted by acting only from theexterior of said ventricular chamber. For example, said anchoring plugcomprises a deformable anchoring device adapted to elastically deform tofit into an inlet opening formed in the heart wall which delimits theventricular chamber of the passive heart to be engaged in undercutagainst a face of the heart wall arranged in undercut with respect tothe outer face of the passive heart.

DRAWINGS

Further features and advantages of the invention shall become readilyapparent from the following description of preferred embodimentsthereof, provided by way of non-limiting example, with reference to theaccompanying drawings, in which:

FIG. 1 is a diagrammatic depiction of a test bench assembly, inaccordance with one embodiment;

FIG. 1 bis is a diagrammatic depiction of a test bench assembly, inaccordance with one embodiment;

FIG. 2 is a diagrammatic depiction of a test bench assembly, inaccordance with one embodiment;

FIG. 3 is a diagrammatic depiction of the operation during the systolephase of a test bench assembly in left heart configuration;

FIG. 4 is a diagrammatic depiction of the operation during the diastolephase of a test bench assembly in left heart configuration;

FIG. 5 is an axonometric view of an anchoring plug, in accordance withone embodiment.

DESCRIPTION OF SOME PREFERRED EMBODIMENTS

In accordance with a general embodiment, a test bench assembly 10 isprovided for the simulation of cardiac surgery and/or interventionalcardiology operations and/or procedures. Said test bench assembly 10 isparticularly suitable to enable the execution of prosthesis tests, testsof new surgical therapies and the training of a cardiacsurgeon/interventional cardiologist, avoiding acting on a living being.

Said test bench assembly 10 comprises a passive heart 12. Said passiveheart 12 is an explanted or artificial or hybrid heart. For example,said passive heart 12 is a heart from an animal donor, for exampleporcine or ovine, or it is a heart from a human donor, or it is anartificial heart. The term “passive” means that said heart does notcarry out the pumping action spontaneously. Said passive heart 12 has atleast one pair of heart chambers 14, 16; 114, 116, said pair of cardiacchambers comprising one atrial chamber 14; 114 and one ventricularchamber 16; 116.

In accordance with one embodiment, said passive heart 12 comprises atleast one heart valve 18; 19; 118. Said heart valve 18; 19; 118 is anative valve, or it is an artificial valve, or it is a hybrid valve. Forexample, said heart valve 18; 118 is a mitral valve 18, interposedbetween left atrial chamber 14 and left ventricular chamber 16. In thiscase, said test bench assembly 10 simulates the left heart.

Preferably, said heart valve 18; 19; 118 is an outflow valve 19,preferably an aortic valve 19 positioned at the output from the leftventricular chamber 16. In accordance with one embodiment, said cardiacvalve is an outflow valve 19, preferably a pulmonary valve, positionedat the output from the right ventricular chamber 116. In accordance withone embodiment, said passive heart 12 comprises at least one section ofblood vessel. In accordance with one embodiment, said passive heart 12comprises a section of aorta and a cardiac valve 19 positioned betweenthe left ventricular chamber 16 and the section of aorta, to simulatethe aortic valve. Preferably, said passive heart 12 comprises at leastone outflow valve 19 positioned downstream of a ventricular chamber ofthe passive heart 12, for example positioned in said at least onesection of blood vessel. Preferably, said outflow valve 19 is adapted toselectively allow the flow of the working fluid 72 out of theventricular chamber of said at least one pair of cardiac chambers of thepassive heart 12.

For example, said passive heart 12 comprises a section of aortic arch,or a section of pulmonary artery, or it comprises a section of venacava. In accordance with one embodiment, said passive heart 12 comprisestwo pairs of heart chambers 14, 16, 114, 116 each comprising one atrialchamber 14; 114 and one ventricular chamber 16; 116, an interatrialseptum 68 which divides the atrial chambers 14, 114 and aninterventricular septum 70 which divides the ventricular chambers 16,116, one heart valve 18; 118 interposed between each atrial chamber 14;114 and each ventricular chamber 16; 116 and sections of blood vesselsconnected to each of the ventricular chambers 16; 116.

Said test bench assembly 10 further comprises a reservoir 20, adapted tohouse the working fluid 72. Preferably, said working fluid 72 is aliquid. For example, said working fluid 72 is a liquid having theviscosity of blood. For example, said working fluid 72 is water or anaqueous solution. The provision of such a test bench assembly 10 tosimulate cardiac surgery and/or interventional cardiology operationsavoiding the need to use blood as a working fluid 72.

Said test bench assembly 10 further comprises a pressure generator 22,adapted to provide the pumping function to said passive heart 12 bypumping said working fluid 72, Said pressure generator 22 is fluidicallyconnected both to said ventricular chamber 16 of said passive heart 12and to said reservoir 20 by means of first fluid connection means 66.

Said test bench assembly 10 further comprises at least one pressureregulation device 24 which provides the working fluid 72 in input to theatrial chamber 14 with the preload pressure and the working fluid inoutput from the left ventricular chamber 16 with the afterload pressure.Preferably, said at least one pressure regulation device 24 provides theworking fluid 72 in input to the left atrial chamber 14 with the preloadpressure, and the working fluid in output from the left ventricularchamber 16 and downstream of the outflow valve 19, for example theaortic valve 19, with the afterload pressure.

Said at least one pressure regulation device 24 is fluidically connectedboth to said left atrial chamber 14 of said passive heart 12 and to saidleft ventricular chamber 16 of said passive heart 12 by means of secondfluid connection means 64.

In accordance with one embodiment, said test bench assembly 10 furthercomprises at least one additional pressure regulation device 124 whichprovides the working fluid in input to the right atrial chamber 114 withthe preload pressure, and the working fluid at the output from the rightventricular chamber 116 with the afterload pressure, in which said atleast one additional pressure regulation device 124 is fluidicallyconnected both to said right atrial chamber 114 of said passive heart 12and to said right ventricular chamber 116 of said passive heart 12 bymeans of second fluid connection means 64. Preferably, said at least oneadditional pressure regulation device 124 provides the working fluid 72in input to the right atrial chamber 114 with the preload pressure, andthe working fluid 72 at the output from the right ventricular chamber116 and downstream of the outflow valve, for example the pulmonaryvalve, with the afterload pressure.

Said at least one pressure regulation device 24 allows to regulate thepressure of the working fluid both at the input and at the output fromthe passive heart 12, to simulate the fluid dynamic impedance of thepreload and afterload pressures observed in vivo.

In accordance with a preferred embodiment, said at least one pressureregulation device 24 comprises a single compliant element 26 for eachpair of cardiac chambers 14, 16; 114, 116, which provides the workingfluid 72 with both the preload and the afterload pressures. Preferably,said compliant element 26 is a container.

Advantageously, said single compliant element 26 for each pair of heartchambers 14, 16 provides the working fluid 72 with both the preload andthe afterload pressures while having reduced size compared to knownsolutions which instead use a first compliant element to provide thepreload and a second compliant element to provide the afterloadpressure. This allows to make the test bench assembly 10 easilytransportable.

The provision of a transportable test bench assembly 10 allows to reducethe operating costs of the test bench, because it is not necessary forclinical personnel, who generally have high hourly costs, to travel tothe place where the test bench assembly 10 is installed, but it allowsto take the test bench to the place where the clinical personnel islocated. In accordance with one embodiment, said test bench assembly 10comprises a support dolly comprising wheels, so as to facilitatetransporting said test bench assembly 10.

With additional advantage, said single compliant element 26 for eachpair of heart chambers 14, 16; 114, 116 allows to provide a pressureregulation device 24 which self-regulates at steady state. This allowsto avoid associating electronic sensors and/or control devices with theat least one pressure regulation device 24; 124. In other words, theprovision of such a single compliant element 26 for each pair of cardiacchambers 14, 16; 114, 116 allows to provide a self-controlled pressureregulation device 24.

In accordance with one embodiment, said compliant element 26 acts as anexpansion vessel or tank. Preferably, the hydrostatic head of saidcompliant element 26 varies when using the test bench assembly 10 toallow the circuit to self-regulate.

In accordance with a preferred embodiment, said at least one pressureregulation device 24 comprises an afterload resistance 30 whichregulates the afterload pressure. By way of non-limiting example, theafterload pressure is between approximately 50 mmHg (millimeters ofmercury) equivalent to approximately 67 millibar and approximately 100mmHg equivalent to approximately 133 millibar, and the preload pressureis between approximately 5 mmHg equivalent to approximately 7 millibarand approximately 15 mmHg equivalent to approximately 20 millibar.

The provision of said afterload resistance 30 allows to generate asystolic pressure in the ventricular chamber 16; 116, for example theleft ventricular chamber 16 of the left heart, which is higher than theafterload pressure, so that the mitral valve 18 closes during thesystolic phase.

In accordance with one embodiment, said second fluid connection means 64comprise a systole branch 32 which fluidically connects, through saidoutflow valve, for example said aortic valve 19, said ventricularchamber 16; 116 of said passive heart 12 to said at least one pressureregulation device 24; 124, and a diastole branch 34 which fluidicallyconnects said at least one pressure regulation device 24; 124 to said atleast one atrial chamber 14; 114 of said passive heart 12. In accordancewith one preferred embodiment, said pressure regulation device 24 allowsto regulate pressure in the segment of the systole branch 32 which isbetween the outflow valve 19 and the afterload resistance 30, both whenthe aortic valve 19 is closed and when the aortic valve 19 is open.Preferably, said segment of the systole branch 32 which is between theoutflow valve 19 and the afterload resistance 30 is positioneddownstream of the outflow valve 19, or aortic valve 19, along saidsystolic path S-S.

In accordance with one embodiment, said systole branch 32 comprises saidafterload resistance 30.

In accordance with one embodiment, said systole branch 32 and saiddiastole branch 34 join in a section 46 which flows into said compliantelement 26.

In accordance with one embodiment, said compliant element 26 is a freesurface vessel. In accordance with one embodiment, said compliantelement 26 is a closed pressurized tank.

Preferably, the working fluid in said compliant element 26 has higherpressure than the working fluid in said reservoir 20. The provision ofsuch a pressure gradient favorably allows to determine a movement bygravity of the working fluid towards said reservoir 20. Thereby, it ispossible to simulate the diastole phase in a passive manner, in otherwords avoiding supplying energy to determine the movement of the workingfluid along the diastolic path D-D.

In accordance with one preferred embodiment, said compliant element 26is a free surface vessel and it is positioned higher than said passiveheart 12 which in turn is positioned lower than said reservoir 20. Inthis way, it is possible to maintain the working fluid under pressure,preventing air from entering into the fluid when the test bench assembly10 is not in use.

A first height difference z1 between the hydrostatic head of saidcompliant element and said passive heart 12, and a second heightdifference z2 between said passive heart 12 and the hydrostatic head ofsaid reservoir 20, and a third height difference z3 between thehydrostatic head of said compliant element 26 and the hydrostatic headof said reservoir 20. Preferably, said first height difference z1 isequal to the sum of said second height difference and of said thirdheight difference z2+z3.

In accordance with a preferred embodiment, said pressure generator 22comprises at least one flow intercepting element 28, which selectivelyenables direct fluid connection between said passive heart 12 and saidreservoir 20.

Preferably, said at least one flow intercepting element 28 comprises atleast one active valve. Preferably, said at least one active valve is atleast one solenoid valve. The provision of a solenoid valve allows toobtain rapid response times of the fluid intercepting element 28.

In accordance with an embodiment, said flow intercepting element 28comprises a two-way solenoid valve. In accordance with an embodiment,said flow intercepting element 28 comprises a three-way solenoid valve.

In accordance with an embodiment, said active valve is a hydrauliccontrol valve. In accordance with an embodiment, said active valve is apneumatic control valve.

In accordance with a preferred embodiment, said pressure generator 22comprises a kinetic stationary flow rate pump 48. The provision of akinetic stationary flow rate pump 48 which cooperates with a flowintercepting element 28 allows to simulate the pressures of the cardiaccycle, without thereby using a programmable pulsatile pump. In this way,a simplified activation of the test bench is allowed, as well as asimplified control in operating conditions, which allows even operatorswho are not qualified in engineering matters to control the activationand operation of the test bench. This allows to reduce the operatingcosts of the test bench.

In accordance with an embodiment, said first fluid connection means 66comprise a reservoir conduit 74, which fluidically connects saidreservoir 20 to said pressure generator 22, said reservoir conduit 74flowing by means of a bifurcation 76 into a pump branch 78, which flowsinto said kinetic stationary flow rate pump 48, and a shunt branch 80,which flows into said flow intercepting element 28 avoiding traversingsaid kinetic stationary flow rate pump 48. Preferably, said kineticstationary flow rate pump 48 is fluidically connected to said flowintercepting element 28 by means of a generator conduit 82.

Such a test bench assembly 10 allows to simulate the systolic phase andthe diastolic phase. As shown for example in FIG. 3 , during thesystolic phase, the pressure generator 22, thrusting the working fluid72 into the ventricular chamber 16; 116, generates a pressure increasein the ventricular chamber 16; 116 which determines the opening of theoutflow valve 19, for example the aortic valve 19 in the case of leftheart, where present, and thrusts the working fluid 72 towards at leastone pressure regulation device 24; 124. In particular, the flow ofworking fluid 72 passes in the systolic branch 32 of said second fluidconnection means 66 and reaches the compliant element 26. The systolicpath S-S of the working fluid is indicated with the arrow S-S in FIG. 3.

As shown for example in FIG. 4 , during the diastolic phase, the workingfluid 72, by effect of gravity, reaches the atrial chamber 14; 114raising pressure inside the atrial chamber 14; 114 which determines theopening of the cardiac valve 18; 118, for example the mitral valve inthe case of left heart. Hence, the working fluid 72 reaches theventricular chamber 16; 116 and, again by gravity, traverses theventricular conduit 36 of said first fluid connection means 66,traverses said flow intercepting element 28, flows through said shuntbranch 80 and reaches the reservoir 20 flowing through said reservoirconduit 74. The diastolic path D-D of the working fluid is indicated inFIG. 4 with the arrow D-D.

In accordance with an embodiment in which said passive heart 12 lacks anartificial or natural aortic valve, the provision of said afterloadresistance 30 avoids having the diastolic path D-D of the working fluid72 include the systole branch 32.

In accordance with an embodiment in which said passive heart 12comprises an artificial or natural aortic valve 19 adapted to direct thepath of the working fluid 72 during the diastolic phase, the closure ofthe aortic valve 19 avoids having the diastolic path D-D include thesystole branch 32.

The provision of said flow intercepting element 28, for example asolenoid valve, allows, during the systolic phase, to connect thekinetic stationary flow rate pump 48 to the fluid circuit, and, duringthe diastolic phase, to disconnect said kinetic stationary flow ratepump 48, to allow the flow towards the reservoir 20. In accordance withan embodiment, the expression “fluid circuit” indicates the useful paththrough which the working fluid can travel in the test bench assembly10.

In accordance with one embodiment, said pressure generator 22 comprisesa recirculation circuit, which allows, during the diastolic phase, tomaintain the kinetic stationary flow rate pump 48 active without therebyincreasing pressure within the fluid circuit. The provision of saidrecirculation circuit allows to obtain a variable flow rate of workingfluid 72 within the ventricular chamber 16 without deactivating saidstationary flow rate pump 48 cooperating with said flow interceptingelement 28.

In accordance with one embodiment, said kinetic stationary flow ratepump 48 is a centrifugal pump. This allows to maintain low theinstallation costs of the test bench assembly 10, without therebyresulting in a decrease in reliability.

In accordance with an embodiment, said test bench assembly 10 comprisesa feedback conduit 62, which connects said compliant element 26 and saidreservoir 20, so that, when the working fluid reaches a predefined valueof pressure inside said compliant element 26, a portion of the workingfluid is sent back into the reservoir 20. This improves theself-regulation of the fluid circuit.

In accordance with an embodiment, said test bench assembly 10 comprisesa control and drive unit 60 associated with said pressure generator 22and comprising at least one programmable logic controller. Preferably,said control and drive unit 60 is adapted to control the activation ofthe flow intercepting element 28, for example a solenoid valve, tosimulate the cardiac cycle. Preferably, said control and drive unit 60is associated with said pressure generator 22 by means of anelectromagnetic connection 84. In accordance with an embodiment, saidcontrol and drive unit 60 associated with said pressure generator 22 bymeans of a wireless electromagnetic connection 84. This allows tocontrol said pressure generator 22 remotely.

In accordance with an embodiment, said test bench assembly 10 comprisesan image acquisition system having at least one probe positionedinternally to at least one between said atrial cavity 14 and saidventricular cavity 16. Preferably, said image acquisition systemcomprises a video probe, adapted to acquire a video of the operation ofportions of the test bench, for example the operation of at least onecardiac valve 18. Alternatively or additionally, said test benchassembly 10 is suitable for displaying with a fluoroscopy acquisitionsystem, adapted to acquire fluoroscopic images. Alternatively oradditionally, said test bench assembly 10 is suitable for displayingwith an ultrasound scan acquisition system, adapted to acquireechocardiographic and/or echo Doppler images.

In accordance with a preferred embodiment, said first fluid connectionmeans 64 comprise at least one ventricular conduit 36 which flows intosaid ventricular chamber 16 of the passive heart 12, and in which saidventricular conduit 36 comprises an anchoring plug 38 which can befitted by acting only from the exterior of said ventricular chamber 16.The provision of such an anchor plug 38 makes the operation ofconnecting the passive heart 12 to said first fluid connection means 66of the test bench quicker compared to known solution, and reliable aswell. In addition, avoiding the need for typically surgical proceduresto connect the ventricular conduit 36 to the passive hear 12, forexample sutures of the ventricular conduit 36 to the passive heart 12,enables personnel who are not qualified, and hence have lower hourlycost than a cardiac surgeon/interventional cardiologist, to connect thepassive heart 12 to the fluid circuit.

In accordance with an embodiment, said anchoring plug 38 comprises adeformable anchoring device 40, adapted to elastically deform to fitinto an inlet opening formed in the heart wall 50 which delimits theventricular chamber 16 of the passive heart 12 to be engaged in undercutagainst a face of the heart wall 50 arranged in undercut with respect tothe outer face of the passive heart. The provision of such an anchoringplug 38 makes the operations for connecting the passive heart 12 to thefluid circuit highly rapid and simple, for example of the“plug-and-play” type. Preferably, said anchoring plug 38 is applied inthe apical portion of the passive heart 12.

Preferably, said test bench assembly 10 comprises a collection tank,adapted to collect any fluid leaks. Generally, fluid leaks areprevalently located in the connecting portion between said first fluidconnection means 64 and said passive heart 12. The provision of saidanchoring plug 38, allowing to avoid connection sutures, allows tosignificantly reduce fluid leaks compared to known solutions.

In accordance with one embodiment, said anchoring plug 38 comprises astem 52 which is internally hollow to allow the passage of the workingfluid, at least one translating fastening ring nut 54 mounted on saidstem 52 and adapted to clamp between the heart wall 50 between a supportsurface 58 of said ring nut and a fastening surface 56 of saiddeformable anchoring device 40, to determine the secure anchoring of theanchoring plug 38 to the passive heart 12. In accordance with anembodiment, said stem 52 is externally threaded and said fastening ringnut 54 acts as a translating leadscrew.

In accordance with an embodiment, said anchoring plug 38 comprises athreaded stem which cooperates with a threaded nut delivered into theventricular chamber 16.

A method for using a test bench shall be described below.

In accordance with a general embodiment, a method for using a test benchassembly for the simulation of cardiac surgery and/or interventionalcardiology operations and/or procedures comprises the following steps.

-   -   providing a passive heart 12;    -   providing a pressure generator 22;    -   providing a reservoir 20 fluidically connected to said pressure        generator 22;    -   making a hole in the heart wall 50 which delimits a ventricular        chamber 18;    -   connecting said pressure generator 22 to said passive heart 12;    -   using a single compliant element 26 connected to an atrial        chamber and a ventricular chamber to provide the working fluid        with the preload pressure and the afterload pressure.

In accordance with a possible operating mode, said method comprises theadditional step of connecting an anchoring plug 38 to said ventricularchamber 16 through said hole in the heart wall 50 acting only from theexterior of the passive heart 12.

In accordance with a possible operating mode, said method comprises theadditional step of using a stationary flow rate pump 48 cooperating witha flow intercepting element 28 to simulate the cardiac flow rate.

Such a test bench assembly 10 is particularly suited, but not univocallyintended, to allow in non-invasive manner and with no need to interveneon living being in any way, to train cardiac surgeons/interventionalcardiologists on at least one of the following medical-surgicaltherapies:

-   -   transcatheter aortic valve implantation through a dummy femoral        artery;    -   transcatheter aortic valve implantation through a dummy        ascending aorta;    -   transcatheter aortic valve implantation from the left ventricle;    -   percutaneous mitral valve implantation from the left ventricle;    -   transcatheter implantation of mitral neochordae from the left        ventricle;    -   percutaneous mitral valve implantation from the fossa ovalis        directly or through a virtual vena cava;    -   transcatheter mitral valve implantation directly from the left        atrium;    -   transcatheter introduction of occluder of the left auricle from        the interatrial septum directly or through virtual vena cava;    -   transcatheter procedures of the tricuspid valve;    -   transcatheter procedures of pulmonary valve;    -   reparative beating heart surgical procedures.

Thanks to the features described above separately or jointly with eachother in particular embodiments, it is possible to obtain a test benchassembly, as well as a method, which at the same time satisfies themutually contrasting needs described above, and the aforementioneddesired advantages, and in particular:

-   -   it is possible to faithfully reproduce the physiological        conditions of beating heart and of blood circulation without        thereby making the test bench assembly 10 bulky or complicated        to operate;    -   it is possible to reduce the installation and operation costs of        the test bench assembly relative to known solutions, without        thereby diminishing functionality or reliability;    -   it is possible to reduce the number of components and the size        of the test bench assembly relative to known solutions, without        thereby diminishing functionality or reliability;    -   it is possible to reproduce the physiological conditions of        beating heart and blood circulation and at the same time to        reduce the costs associated with the procedures to train cardiac        surgeons/interventional cardiologists.

Those skilled in the art may make several changes and adaptations to theembodiments described above in order to meet contingent and specificneeds, and can replace elements with others which are functionallyequivalent, without however departing from the scope of the followingclaims.

LIST OF REFERENCES

-   -   10 Test bench assembly    -   12 Passive heart    -   14 Left atrial chamber    -   16 Left ventricular chamber    -   18 Mitral heart valve, or mitral valve    -   19 Outflow valve, or aortic heart valve, or aortic valve    -   20 Reservoir    -   22 Pressure generator    -   24 Pressure regulation device    -   26 Compliant element    -   28 Flow intercepting element    -   30 Afterload resistance    -   32 Systole branch    -   34 Diastole branch    -   36 Ventricular conduit    -   38 Anchoring plug    -   40 Deformable anchoring device    -   46 Section    -   48 Kinetic stationary flow rate pump    -   50 Heart wall    -   52 Stem    -   54 Fastening ring nut    -   56 Fastening surface    -   58 Ring nut support surface    -   60 Control and drive unit    -   62 Feedback conduit    -   64 First fluid connection means    -   66 Second fluid connection means    -   68 Atrial septum    -   70 Ventricular septum    -   72 Working fluid    -   74 Reservoir conduit    -   76 Bifurcation    -   78 Pump branch    -   80 Shunt branch    -   82 Generator conduit    -   84 Electromagnetic connection    -   114 Atrial chamber, or right atrial chamber    -   116 Ventricular chamber, or right ventricular chamber    -   118 Tricuspid heart valve, or tricuspid valve    -   124 Additional pressure regulation device    -   S-S Systole path    -   D-D Diastole path    -   z1 First height difference    -   z2 Second height difference    -   z3 Third height difference

1. A test bench assembly (10) for the simulation of cardiac surgeryand/or interventional cardiology operations and/or procedures,comprising: a passive heart (12), wherein said passive heart (12) is anexplanted or artificial or hybrid heart, said passive heart (12) havingat least one pair of cardiac chambers (14, 16; 114, 116) comprising anatrial chamber (14; 114) and a ventricular chamber (16; 116); saidpassive heart (12) further comprising at least one outflow valve (19)positioned at the outlet of said ventricular chamber of said at leastone pair of cardiac chambers; a reservoir (20), adapted to house theworking fluid; a pressure generator (22), adapted to provide saidpassive heart (12) with the pumping function by pumping said workingfluid, said pressure generator (22) being fluidically connected both tosaid ventricular chamber (16; 116) of said passive heart (12) by meansof at least one ventricular conduit (36) and to said reservoir (20) bymeans of a reservoir conduit (74); at least one pressure regulationdevice (24; 124) which provides the working fluid (72) in input to theatrial chamber (14; 114) with the preload pressure and the working fluid(72) in output from the ventricular chamber (16; 116) and downstream ofthe outflow valve (19) with the afterload pressure; said at least onepressure regulation device (24; 124) being fluidically connected both tosaid atrial chamber (14; 114) of said passive heart (12) by means of adiastole branch (34) and to said ventricular chamber (16; 116) of saidpassive heart (12) through said outflow valve (19), by means of asystole branch; characterized in that said at least one pressureregulation device (24; 124) comprises a single compliant element (26)for each pair of cardiac chambers (14, 16; 114, 116), said singlecompliant element (26) acting as an expansion vessel, said singlecompliant element (26) providing the working fluid (72) with both thepreload pressure and the afterload pressure.
 2. A test bench assembly(10) according to claim 1, wherein said at least one pressure regulationdevice (24; 124) comprises an afterload resistance (30) which regulatesthe afterload pressure.
 3. A test bench assembly (10) according to claim1 or 2, wherein said compliant element (26) is a free surface vessel ora closed pressurized tank.
 4. A test bench assembly (10) according toany one of the preceding claims, wherein said outflow valve (19) is anaortic valve (19) or is a pulmonary valve.
 5. A test bench assembly (10)according to any one of the preceding claims, wherein the working fluid(72) in said compliant element (26) has a higher pressure than theworking fluid (72) in said reservoir (20).
 6. A test bench assembly (10)according to any one of the preceding claims, wherein said systolebranch (32) comprises said afterload resistance (30).
 7. A test benchassembly (10) according to any one of the preceding claims, wherein saidsystole branch (32) and said diastole branch (34) are joined in asection (46) which flows into said compliant element (26).
 8. A testbench assembly (10) according to any one of the preceding claims,wherein said pressure generator (22) comprises at least one flowintercepting element (28), which selectively allows the direct fluidconnection between said passive heart (12) and said reservoir (20).
 9. Atest bench assembly (10) according to claim 8, wherein said at least oneflow intercepting element (28) comprises at least one active valve. 10.A test bench assembly (10) according to claim 9, wherein said at leastone active valve is at least one solenoid valve.
 11. A test benchassembly (10) according to any one of the preceding claims, wherein saidpressure generator (22) comprises a kinetic stationary flow rate pump(48).
 12. A test bench assembly (10) according to claim 11, wherein saidkinetic stationary flow rate pump (48) is a centrifugal pump.
 13. A testbench assembly (10) according to any one of the preceding claims,wherein said ventricular conduit (36) comprises an anchoring plug (38)which can be fitted by acting only from the exterior of said ventricularchamber (16; 116).
 14. A test bench assembly (10) according to claim 13,wherein said anchoring plug (38) comprises a deformable anchoring device(40) adapted to elastically deform to fit into an inlet opening formedin the heart wall (50) which delimits the ventricular chamber (16; 116)of the passive heart (12) to be engaged in undercut against a face ofthe heart wall (50) arranged in undercut with respect to the outer faceof the passive heart (12).
 15. A test bench assembly (10) according toany one of the preceding claims, comprising a control and drive unit(60) associated with said pressure generator (22) and comprising atleast one programmable logic controller.